Structural Complexity and Decay in FLOSS Systems: An Inter-Repository Study

Past software engineering literature has firmly established that software architectures and the associated code decay over time. Architectural decay is, potentially, a major issue in Free/Libre/Open Source Software (FLOSS) projects, since developers sporadically joining FLOSS projects do not always have a clear understanding of the underlying architecture, and may break the overall conceptual structure by several small changes to the code base. This paper investigates whether the structure of a FLOSS system and its decay can also be influenced by the repository in which it is retained: specifically, two FLOSS repositories are studied to understand whether the complexity of the software structure in the sampled projects is comparable, or one repository hosts more complex systems than the other. It is also studied whether the effort to counteract this complexity is dependent on the repository, and the governance it gives to the hosted projects. The results of the paper are two-fold: on one side, it is shown that the repository hosting larger and more active projects presents more complex structures. On the other side, these larger and more complex systems benefit from more anti-regressive work to reduce this complexity

Quality factors and coding standards - a comparison between open source forges

Enforcing adherence to standards in software development in order to produce high quality software artefacts has long been recognised as best practice in traditional software engineering. In a distributed heterogeneous development environment such those found within the Open Source paradigm, coding standards are informally shared and adhered to by communities of loosely coupled developers. Following these standards could potentially lead to higher quality software. This paper reports on the empirical analysis of two major forges where OSS projects are hosted. The first one, the KDE forge, provides a set of guidelines and coding standards in the form of a coding style that developers may conform to when producing the code source artefacts. The second studied forge, SourceForge, imposes no formal coding standards on developers. A sample of projects from these two forges has been analysed to detect whether the SourceForge sample, where no coding standards are reinforced, has a lower quality than the sample from KDE. Results from this analysis form a complex picture; visually, all the selected metrics show a clear divide between the two forges, but from the statistical standpoint, clear distinctions cannot be drawn amongst these quality related measures in the two forge samples

Structural Complexity and Decay in FLOSS Systems: An Inter-Repository Study

Past software engineering literature has firmly established that software architectures and the associated code decay over time. Architectural decay is, potentially, a major issue in Free/Libre/Open Source Software (FLOSS) projects, since developers sporadically joining FLOSSprojects do not always have a clear understanding of the underlying architecture, and may break the overall conceptual structure by several small changes to the code base. This paper investigates whether the structure of a FLOSS system and its decay can also be influenced by the repository in which it is retained: specifically, two FLOSS repositories are studied to understand whether the complexity of the software structure in the sampled projects is comparable, or one repository hosts more complex systems than the other. It is also studied whether the effort to counteract this complexity is dependent on the repository, and the governance it gives to the hosted projects. The results of the paper are two-fold: on one side, it is shown that the repository hosting larger and more active projects presents more complex structures. On the other side, these larger and more complex systems benefit from more anti-regressive work to reduce this complexity

Evolutionary success of open source software: an investigation into exogenous drivers

The “success” of a Free/Libre/Open Source Software (FLOSS) project has often been evaluated through the number of commits made to its configuration management system, number of developers and number of users. Based on SourceForge, most studies have concluded that the vast majority of projects are failures. This paper argues that the relative success of a FLOSS project can depend also on the chosen forge and distribution. Given a random sample of 50 projects contained within a popular FLOSS forge (Debian, which is the basis of the successful Debian distribution), we compare these with a similar sample from SourceForge, using product and process metrics, such as size achieved and number of developers involved. The results show firstly that, depending on the forge of FLOSS projects, researchers can draw different conclusions regarding what constitutes a successful FLOSS project. Secondly, the projects included in the Debian distribution benefit, on average, from more evolutionary activity and more developers than the comparable projects on SourceForge. Finally, the Debian projects start to benefit from more activity and more developers from the point at which they join this distribution

Identifying exogenous drivers and evolutionary stages in FLOSS projects

The success of a Free/Libre/Open Source Software (FLOSS) project has been evaluated in the past through the number of commits made to its configuration management system, number of developers and num- ber of users. Most studies, based on a popular FLOSS repository (SourceForge), have concluded that the vast majority of projects are failures. This study's empirical results confirm and expand conclusions from an earlier and more limited work. Not only do projects from different repositories display different process and product characteristics, but a more general pattern can be observed. Projects may be considered as early inceptors in highly visible repositories, or as established projects within desktop-wide projects, or finally as structured parts of FLOSS distributions. These three possibilities are formalized into a framework of transitions between repositories. The framework developed here provides a wider context in which results from FLOSS repository mining can be more effectively presented. Researchers can draw different conclusions based on the overall char- acteristics studied about an Open Source software project's potential for success, depending on the repos- itory that they mine. These results also provide guidance to OSS developers when choosing where to host their project and how to distribute it to maximize its evolutionary success

Quality factors and coding standards - a comparison between open source forges

Enforcing adherence to standards in software development in order to produce high quality software artefacts has long been recognised as best practice in traditional software engineering. In a distributed heterogeneous development environment such those found within the Open Source paradigm, coding standards are infor-mally shared and adhered to by communities of loosely coupled developers. Following these standards could potentially lead to higher quality software. This paper reports on the empirical analysis of two major forges where OSS projects are hosted. The first one, the KDE forge, provides a set of guidelines and coding standards in the form of a coding style that developers may conform to when producing the code source artefacts. The second studied forge, SourceForge, imposes no formal coding standards on developers. A sample of projects from these two forges has been analysed to detect whether the SourceForge sample, where no coding standards are reinforced, has a lower quality than the sample from KDE. Results from this analysis form a complex picture; visually, all the selected metrics show a clear divide between the two forges, but from the statistical standpoint, clear distinctions cannot be drawn amongst these quality related measures in the two forge samples

Evolutionary success of Open Source Software: an investigation into exogenous drivers

The “success” of a Free/Libre/Open Source Software (FLOSS) project has often been evaluated through the number of commits made to its configuration management system, number of developers and number of users. Based on Source- Forge, most studies have concluded that the vast majority of projects are failures. This paper argues that the relative success of a FLOSS project can depend also on the chosen forge and distribution. Given a random sample of 50 projects contained within a popular FLOSS forge (Debian, which is the basis of the successful Debian distribution), we compare these with a similar sample from SourceForge, using product and process metrics, such as size achieved and number of developers involved. The results show firstly that, depending on the forge of FLOSS projects, researchers can draw different conclusions regarding what constitutes a successful FLOSS project. Secondly, the projects included in the Debian distribution benefit, on average, from more evolutionary activity and more developers than the comparable projects on SourceForge. Finally, the Debian projects start to benefit from more activity and more developers from the point at which they join this distribution

Determining crystal structures through crowdsourcing and coursework

We show here that computer game players can build high-quality crystal structures. Introduction of a new feature into the computer game Foldit allows players to build and real-space refine structures into electron density maps. To assess the usefulness of this feature, we held a crystallographic model-building competition between trained crystallographers, undergraduate students, Foldit players and automatic model-building algorithms. After removal of disordered residues, a team of Foldit players achieved the most accurate structure. Analysing the target protein of the competition, YPL067C, uncovered a new family of histidine triad proteins apparently involved in the prevention of amyloid toxicity. From this study, we conclude that crystallographers can utilize crowdsourcing to interpret electron density information and to produce structure solutions of the highest quality